Dobro started its serial numbers around 800. Later in the ’30s Regal in Chicago confused things by numbering a run of Dobros across the same range. An early California instrument can be identified by square slot-ends in the headstock, coverplate screws in the points of numbers on a clock, and the lack of a dot at the 17th fret. National Guitar makers of fine reso-phonic guitars, hand crafted in California.

Serial Numbers For Electronics

National Duolian Serial Numbers C 9169

This is a clean example of a 14-fret, rolled f-hole single cone Duolian. By 1936, National left the slotted head stock behind and began offering guitars with the 'modern' solid head stock, as on this example. The four digit serial number dates this one to 1936. The guitar appears all original. The paint still sparkles, showing only a bit of wear along the edge of the top, and on the cover plate. In this time frame, National went away from the 'ribbed' cover plate offered on the single cone guitars in the prior four years. The body is dent free. The neck appears to be basswood, with a Brazilian rosewood fingerboard. The back of the neck shows some playing wear. The Duolian decal on the headstock remains in excellent condition, and creates an attractive look along with the sunburst paint. The plating on the tuners and tail piece is still very good. The lower frets show some play-wear divots. The fingerboard measures about a 10 degree radius and the action is set at a hair over 5/64' with a straight neck, making the guitar eminently playable. The sound produced is the quintessential National wail. Comes with a new hard case. Please check the mp3 sound clip.